In 1344 a Crusade, in which Venice, the Cypriots, and the Hospitallers all joined, ended in the conquest of Smyrna; in 1345 another Crusade, led by Humbert, dauphin of Vienne, ended in failure.
If the dauphin did escape, it seems probable that he perished shortly afterwards or lived in a safe obscurity.
John endeavoured to strengthen his position by marrying his daughter Margaret to the dauphin Louis, and by betrothing his son Philip to a daughter of Charles VI.
But an arrangement was effected in October 1405, and in 1406 John was made by royal decree guardian of the dauphin and the king's children.
The king a prisoner, the dauphin discredited and deserted, and the nobility decimated, The states the peoplethat is to say, the states-generalcould 1356 raise their voice.
It was he who effected a reconciliation between the king and the dauphin after the revolt of the latter.
He was a missionary to the Indians when the prince de Joinville, son of Louis Philippe, met him, and after some conversation asked him to sign a document abdicating his rights in favour of Louis Philippe, in return for which he, the dauphin (alias Eleazar Williams), was to receive the private inheritance which was his.
That there was fraud, and complicated fraud, in the guardians of the dauphin may be taken as proved by a succession of writers from 1850 onwards, and more recently by Frederic Barbey, who wisely attempts no ultimate solution.
This position, however, did not prevent him from negotiating both with the dauphin and with the English; terms were soon arranged with the former, and Charles, having lost much of his popularity, left Paris just before the murder of Marcel in July 1358.
At the meeting of the estates which opened in Paris in October 1356 Le Coq played a leading role and was one of the most outspoken of the orators, especially when petitions were presented to the dauphin Charles, denouncing the bad government of the realm and demanding the banishment of the royal councillors.